Question

Explain why it is preferable to use several graphite electrodes as anodes instead of the single electrode during the above electrolysis.

Answer 1

1. In the electrolysis of Aluminum from its ore Bauxite, the anode used is Graphite or Carbon rods.
2. The Oxygen produced during the electrolysis process will react with the Carbon rods and thereby producing Carbon dioxide gas,
3. Since, this reaction will destroy the graphite rods.
4. So if a single electrode is used there will not be any anode left for performing the reaction.
5. So it is necessary to use several graphites during the electrolysis process.
6. The reaction is,$\underset{Carbon}{C\left(s\right)}+\underset{Oxygen}{O_2\left(g\right)}\to \underset{Carbondioxide}{C{O}_2\left(g\right)}$.
7. Since graphite or carbon rods react with Oxygen which will destroy the anode electrode, it is necessary to use several graphite rodes as an anode.